Flow in porous media

Watering a plant is an everyday choir we do without seeing the complexity in it, probably since it is not a lot of water so we can water some more. But what if we have a field of plants we need to irrigate and not enough water, then we should really optimize our irrigation. For that, we need to understand the complex physics behind flow in porous media.

Multiphase flow in porous media

When we are brewing coffee in a peculator we are actually extracting soluble oil from the ground beans. At first, the pushing water does not reach all the coffee grinds but rather they flow in a small area of the grinds. In time they will expand and extract the rest of the oil. We are interested at these long time scales where one phase replaces the other, and it has important implication not just for our morning coffee but also for CO2 sequestration and to your oil price at your gas station.

Surfactants, oil, and jumps!

Surfactants keep us clean since they are the ingredient in every soap and detergent, but they are naturally occurring in every natural system. Surfactants are molecules with hydrophobic and hydrophilic ends, and as such they are abundant in water-oil interfaces, effectively reducing the interfacial tension between them. Are they uniform in these interfaces? What influence them? These questions are not only relevant to our hygiene but also fundamental for multiphase flow in porous media since they control these marvels capillary instability known as Haines jumps.

Reactive transport

Groundwater makes the majority of accessible fresh water in the world, yet we do a poor job in keeping them fresh. While anthropogenic pollution contaminants them, over-pumping from coastal aquifers salinize them due to seawater intrusions. During these processes, the contaminations and saline water react with the fresh water in unforeseen ways. We aim to understand the physical aspects behind the mixing and reaction in this process.

The fracturing of porous media and how it may lead to earthquakes.

On September 3, 2016, a 5.8 magnitude earthquake occurred near Pawnee, Oklahoma. It wasn’t the first earthquake but the strongest one. Evidence shows that the source of these earthquakes in Oklahoma is anthropogenic. Welcome to the fascinating world of induced seismicity where burial of wastewater from oil production in one spot leads to an earthquake more than a kilometer away. This happens since the access pressure doesn’t advance uniformly, it percolates and even fractures the porous material in its way to a pre-existing fault.

In the movie, you can see a lab experiment where another liquid replaces the fluid in a brittle, porous media, zooming in with a microscope we can see beads separating and fracturing. Therefore, it seems that the fluid is fracturing its way to the fault!